Coldplay front man Chris Martin admits he was a late bloomer, usmagazine.com reports.

“I had a tricky time with girls until I was, like, 21. I got trapped in the friendship tip many, many times,” he tells Rolling Stone. “It was like, ‘I need to be a rock star because this is no good: Being the kind of guy that everybody likes but no one wants to have sex with.’”

Still, Martin admits he hasn’t had a lot of hot-and-heavy romances in his life. He says his wife Gwyneth Paltrow is his only “serious relationship.”

He adds he enjoys the challenge of being married to the Oscar-winning actress.

“I always felt it would be great to be with a very powerful woman because it would keep you in your place,” he says. “Being married to someone very successful and very powerful basically keeps you hungry to improve.”